[PATCH 5.10 400/406] platform/mellanox: mlxbf-tmfifo: Drop jumbo frames

Greg Kroah-Hartman
2023-09-17T19:43:24Z

From: Liming Sun <limings@nvidia.com>

[ Upstream commit fc4c655821546239abb3cf4274d66b9747aa87dd ]

This commit drops over-sized network packets to avoid tmfifo
queue stuck.

Fixes: 1357dfd7261f ("platform/mellanox: Add TmFifo driver for Mellanox BlueField Soc")
Signed-off-by: Liming Sun <limings@nvidia.com>
Reviewed-by: Vadim Pasternak <vadimp@nvidia.com>
Reviewed-by: David Thompson <davthompson@nvidia.com>
Link: https://lore.kernel.org/r/9318936c2447f76db475c985ca6d91f057efcd41.1693322547.git.limings@nvidia.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/platform/mellanox/mlxbf-tmfifo.c | 24 +++++++++++++++++-------
1 file changed, 17 insertions(+), 7 deletions(-)

diff --git a/drivers/platform/mellanox/mlxbf-tmfifo.c b/drivers/platform/mellanox/mlxbf-tmfifo.c
index 42fcccf06157f..194f3205e5597 100644
--- a/drivers/platform/mellanox/mlxbf-tmfifo.c
+++ b/drivers/platform/mellanox/mlxbf-tmfifo.c
@@ -205,7 +205,7 @@ static u8 mlxbf_tmfifo_net_default_mac[ETH_ALEN] = {
static efi_char16_t mlxbf_tmfifo_efi_name[] = L"RshimMacAddr";

/* Maximum L2 header length. */
-#define MLXBF_TMFIFO_NET_L2_OVERHEAD 36
+#define MLXBF_TMFIFO_NET_L2_OVERHEAD (ETH_HLEN + VLAN_HLEN)

/* Supported virtio-net features. */
#define MLXBF_TMFIFO_NET_FEATURES \
@@ -623,13 +623,14 @@ static void mlxbf_tmfifo_rxtx_word(struct mlxbf_tmfifo_vring *vring,
* flag is set.
*/
static void mlxbf_tmfifo_rxtx_header(struct mlxbf_tmfifo_vring *vring,
- struct vring_desc *desc,
+ struct vring_desc **desc,
bool is_rx, bool *vring_change)
{
struct mlxbf_tmfifo *fifo = vring->fifo;
struct virtio_net_config *config;
struct mlxbf_tmfifo_msg_hdr hdr;
int vdev_id, hdr_len;
+ bool drop_rx = false;

/* Read/Write packet header. */
if (is_rx) {
@@ -649,8 +650,8 @@ static void mlxbf_tmfifo_rxtx_header(struct mlxbf_tmfifo_vring *vring,
if (ntohs(hdr.len) >
__virtio16_to_cpu(virtio_legacy_is_little_endian(),
config->mtu) +
- MLXBF_TMFIFO_NET_L2_OVERHEAD)
- return;
+ MLXBF_TMFIFO_NET_L2_OVERHEAD)
+ drop_rx = true;
} else {
vdev_id = VIRTIO_ID_CONSOLE;
hdr_len = 0;
@@ -665,16 +666,25 @@ static void mlxbf_tmfifo_rxtx_header(struct mlxbf_tmfifo_vring *vring,

if (!tm_dev2)
return;
- vring->desc = desc;
+ vring->desc = *desc;
vring = &tm_dev2->vrings[MLXBF_TMFIFO_VRING_RX];
*vring_change = true;
}
+
+ if (drop_rx && !IS_VRING_DROP(vring)) {
+ if (vring->desc_head)
+ mlxbf_tmfifo_release_pkt(vring);
+ *desc = &vring->drop_desc;
+ vring->desc_head = *desc;
+ vring->desc = *desc;
+ }
+
vring->pkt_len = ntohs(hdr.len) + hdr_len;
} else {
/* Network virtio has an extra header. */
hdr_len = (vring->vdev_id == VIRTIO_ID_NET) ?
sizeof(struct virtio_net_hdr) : 0;
- vring->pkt_len = mlxbf_tmfifo_get_pkt_len(vring, desc);
+ vring->pkt_len = mlxbf_tmfifo_get_pkt_len(vring, *desc);
hdr.type = (vring->vdev_id == VIRTIO_ID_NET) ?
VIRTIO_ID_NET : VIRTIO_ID_CONSOLE;
hdr.len = htons(vring->pkt_len - hdr_len);
@@ -723,7 +733,7 @@ static bool mlxbf_tmfifo_rxtx_one_desc(struct mlxbf_tmfifo_vring *vring,

/* Beginning of a packet. Start to Rx/Tx packet header. */
if (vring->pkt_len == 0) {
- mlxbf_tmfifo_rxtx_header(vring, desc, is_rx, &vring_change);
+ mlxbf_tmfifo_rxtx_header(vring, &desc, is_rx, &vring_change);
(*avail)--;

/* Return if new packet is for another ring. */
--
2.40.1